1. Field of the Invention
The present invention relates to a method for controlling opening/closing of cool air discharge ports for supplying a cooling compartment of a refrigerator with cool air.
2. Related Art
In general, as shown in FIG. 1, a refrigerator has a compressor 14 for compressing refrigerant, an evaporator 7 for generating cool air by evaporating the refrigerant supplied from the compressor 14, and a fan 10 for blowing the cool air generated by the evaporator 7. A duct member 12 for forming a cool air duct is installed at the rear part of a fresh food compartment 3. The duct member 12 has a plurality of cool air discharge ports 13 opened in the fresh food compartment 3. The cool air blown by the fan 10 flows into the cool air duct, and then is supplied into the fresh food compartment 3 through the cool air discharge ports 13.
The fresh food compartment 3 is opened and closed by a door 2, and the fresh food compartment 3 is partitioned into a plurality of spaces by shelves 4. At the upper part of the fresh food compartment 3, a cover 5 for shielding the evaporator 7 is installed. The evaporator 7 is fixed by a holder 8 in a space 6 formed by the cover 5.
While the refrigerator operates, frost is generated on the evaporator 7. The cooling efficiency of the evaporator 7 is lowered by the frost. Hence, the refrigerator is equipped with a heater 9 for removing the frost, and performs defrosting operation by heating the evaporator 7 using the heater 9 when the refrigerator is used more than a predetermined period of time.
In the fresh food compartment 3, a temperature sensor (not shown) is installed. When the temperature measured by the temperature sensor is higher than a temperature set by a user, the refrigerator begins to operate the compressor 14 and the fan 10. Then the evaporator 7 generates cool air, and the cool air is supplied into the cool air duct by the fan 10. The cool air supplied into the cool air duct is discharged into the fresh food compartment 3 through the cool air discharge ports 13, and thereby the food stored in the fresh food compartment 3 is cooled.
Meanwhile, a refrigerator equipped with a device for controlling the amount of cool air supplied through the cool air discharge ports 13 has been proposed. Such a device (not shown) is comprised of an opening/closing member disposed near the duct member 12 and a motor for driving the opening/closing member. The refrigerator drives the motor so that the cool air discharge ports 13 are opened or closed by the opening/closing member according to the temperature in the fresh food compartment 3. Then the amount of the cool air supplied into the fresh food compartment 3 is controlled.
However, in such a conventional refrigerator, there is a problem that the temperature in the fresh food compartment 3 cannot be maintained uniform since the opening/closing member merely performs opening or closing operation of the cool air discharge ports 13. In other words, when the cool air discharge ports 13 are open, the cool air is concentrated on an area adjacent to the cool air discharge ports 13, so the area adjacent to the cool air discharge ports 13 is apt to be overcooled in comparison with the area adjacent to the door 2.
Moreover, if the temperature in the fresh food compartment 3 is measured in a specific position at which temperature is high, the cool air is continuously supplied into the fresh food compartment 3 until the temperature of the measuring position reaches to the temperature set by the user, so the food placed at the other positions may be overcooled.